FromQuery? FromBody? What are these ASP.NET Core Web API attributes?

FromQuery and FromBody are some of the attributes that can be placed on a parameter in an controller's action.

These attributes can be used in an ASP.NET Core Web API or MVC app and it helps to bind a parameter against a value which is part of the HTTP request.

The attributes we will look at are:

► FromQuery - Binds a parameter from the query string
► FromHeader - Binds a parameter from the header
► FromForm - Binds a parameter from a form field if the multipart/form-data or x-www-url-encoded content type is used in the request
► FromRoute - Binds a parameter from a route attribute
► FromBody - Binds a parameter when the application/json content type is used in the request and JSON formatted content is part of the body

There is also a FromServices attribute. However, this binds an instance that has been added to the IoC container as part of dependency injection.

This video will show you a C# example of each one and how to test it using Postman.

In-addition, we'll have a look at the ApiController attribute and how the features and behaviour of a controller are changed with this attribute.

💻 Download the code example for this tutorial💻

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► More information:

► Chapters
0:00 The ASP.NET Core attributes we will use
0:19 Learn with .NET courses
0:29 Create controller
1:12 FromQuery attribute
3:01 FromHeader attribute
5:09 FromForm attribute
7:11 FromRoute attribute
9:12 FromServices attribute
12:23 FromBody attribute
14:57 What's included with the code sample

#webapi #mvc #dotnet

[DarshanaHashendra]

Great content. keep up the good work. Cheers.

[arsbkhan]

This is really helpfull.. Could you expand on this and include IFroms and IFormCollections or how to upload files with DTO

[henryespinozat]

Question: when we use [fromquery] but i need to recive more than one parameters, do a have to create a class? or in a method i can declare [fromquery] many time?

[oscarlemdi]

hello good afternoon David,

I have a doubt, how can I specify a specific Content-Type ? for example in one end point I want to receive an application/json and in another one a text/plain.